"WP:HIDDEN" redirects here. For the guideline against hiding content in articles, see MOS:DONTHIDE. For information about hidden categories, see WP:HIDDENCAT. For information about how to hide/show collapsed text, see Template:Hidden.
This page in a nutshell: Hidden text, that is visible only when editing, can be inserted into articles, project pages, and other Wikipedia pages, by surrounding the text as follows: <!-- Hidden text -->
Instructing others how to edit a page that may be difficult to edit
Providing information to assist other editors in preventing a common mistake. For example, if there is a reference which is known to be wrong, it may be appropriate to let other editors know about the error to prevent a likely re-insertion of the error.
Informing other editors that a section title is linked from a redirect, so that if the title is altered, the redirect can be changed.
Letting others know of a better article or location within the article to add information on a current event or other hot topic where there is temptation to add it in that location
Letting others know the location of a template that is included on a page, most commonly an embedded list.
Reminding others of Wikipedia policies where they have been frequently broken. For example, in many articles, hidden text is necessary to remind editors not to add inappropriate links. On the page Help:Getting started, hidden text is used to let others know not to write their first article on that page.
Preparing small amounts of information to be added to the article in the future (such as when a known event will occur). Larger amounts of information should be prepared on a subpage of the article's talk page or in user space.
Hiding a portion of the text that has been temporarily removed while consensus is pending. However, it may be preferable to transfer such text onto a subpage of the article's talk page.
Telling others not to perform certain edits to a page, unless there is an existing guideline or policy against that edit.
When it is a mere local consensus that a certain edit should not be performed, the hidden text should be worded more softly to suggest to the editor to consult the talk page (or archive page if appropriate) for the current consensus prior to making the edit. Since consensus can change, it is inappropriate to use hidden text to try to prohibit making a certain edit merely because it would conflict with an existing consensus.